I am a new player and level 13 mercenary. I am really bad at combat but one think I noticed that my rail shot is always dimmed out. I never use it. it says you can use it only on incapacitated enemies. I guess, my question is how do I do that? is there another activity that is combo'ed with rail shot. I would also appreciate if someone can tell me what are popular combos for BH ? thanks:)

Well, rail shot also works on players with dots (damages over time). If you spec pyro or shield tech, your cylinder will put dots on your opponents as you use moves like rapid shots and flame burst for pyro, or rapid shots and rocket punch for shield tech. If you spec arsenal, you need to put a tracer missile on them first, that leaves you able to rail shot them. In the off chance you spec advanced prototype, you need to hit them with retractable blade first before you rail shot.

The only way to use railshot on an enemy as a merc is:

 

Stunned by Electro Dart (Lv 12?)

Stunned by Concussion Missile (Lv 22)

Stunned by Explosive Dart (Weak and standard only) (Lv 5?)

Stunned by Unload (Weak and standard only) (Lv 3)

Burned by Combustable Gas Cylinder (Lv 6?)

Burned by Fusion missile (Lv 18)

Burned by Incendiary Missile (Lv 20)

Has a heat signature from Tracer MIssile (Lv 20)

In 2.0 Burned by Thermal Detonator (Lv 40)

Stunned by Thermal Detonator (Lv 40)

 

^That's pretty much it.

Edited March 29, 2013 by Zunayson

Once you get Tracer Missile, you will use RS a lot more often.

 

I don't recall what level you get it at but whenever you cast Tracer, an armor debuff will show up on your enemy's bar and a reddish buff will show up on yours - the buff increases RS damage

For Arsenal spec the most important ability that allows the use of rail shot is the Tracer Missile.

 

 

For Pyrotech spec the most important abilities that allow Rail shot are your burn effects. Primarily Incendiary missile once you get that or in some other cases the burn caused by Combustible Gas Cylinder.

Note that at least for pyro spec you should always make sure that you have your own burn dots on the target before Rail shot, since even though any kind of stun or damage over time effect (including those done by other classes or companions) will allow the use of rail shot, the rail shot for pyro spec will do extra damage and will vent some heat only if you have your own burn dots on the target.

 

 

Both Tracer Missile and Incendiary Missile are third tier talents in their skill trees, meaning the earliest you can get them is at level 20 if you put all the points in the same tree as you should.

Edited March 30, 2013 by Eternalnight

The only way to use railshot on an enemy as a merc is:

 

Stunned by Electro Dart (Lv 12?)

Stunned by Concussion Missile (Lv 22)

Stunned by Explosive Dart (Weak and standard only) (Lv 5?)

Stunned by Unload (Weak and standard only) (Lv 3)

Burned by Combustable Gas Cylinder (Lv 6?)

Burned by Fusion missile (Lv 18)

Burned by Incendiary Missile (Lv 20)

Has a heat signature from Tracer MIssile (Lv 20)

In 2.0 Burned by Thermal Detonator (Lv 40)

Stunned by Thermal Detonator (Lv 40)

 

^That's pretty much it.

 

You can also do it to targets that are knocked down by Missile Blast or Death From Above.

Mako, Torian, and Gault all have damage-over-time abilities that can enable the use of your Rail Shot. Gault's acid bomb is actually an AoE DoT.